Saccharomyces cerevisiae as a probiotic agent and a possible aflatoxin B1 adsorbent in simulated fish intestinal tract conditions / Saccharomyces cerevisiae como agente probiótico e possível adsorvente de aflatoxina B1 em condições simuladas do trato intestinal de peixes

The aim of this study was to evaluate in vitro the probiotic potential and absorption of Saccharomyces cerevisiae for the aflatoxin B1 in simulated fish intestinal tract conditions. Three yeast strains were used, two from brewery: S. cerevisiae RC1 and S. cerevisiae RC3 and one from a fish farming environment: S. cerevisiae A8L2. The selected yeasts were subjected to the following in vitro tests: homologous inhibition, self-aggregation, co-aggregation, antibacterial activity, gastrointestinal conditions tolerance and adsorption of AFB1. All S. cerevisiae strains showed good capability of self-aggregation and co-aggregation with pathogenic bacteria. All yeast strains were able to survive the gastrointestinal conditions. In acidic conditions, the factors (strain vs. time) had interaction (P=0.0317), resulting in significant variation among the strains tested in the time periods analyzed. It was observed that there was also interaction (P=0.0062) in intestinal conditions, with an increased number of cells in the 12-hour period for all strains tested. In the adsorption test, the A8L2 strain was statistically more effective (P<0.005) for both AFB1 concentrations evaluated in this study (10 and 25ng/mL). Thus, it was observed that the strains of S. cerevisiae have potential probiotic and adsorbent of AFB1.(AU)

Objetivou-se, com esta pesquisa, avaliar in vitro o potencial probiótico e adsorvente de Saccharomyces cerevisiae para aflatoxina B1 em condições simuladas do trato intestinal de peixes. Foram utilizadas três cepas de leveduras, sendo duas provenientes de cervejaria: S. cerevisiae RC1 e S. cerevisiae RC3, e uma de ambiente de piscicultura: S. cerevisiae A8L2. As leveduras selecionadas foram submetidas aos seguintes testes in vitro: inibição homóloga, autoagregação, coagregação, atividade antibacteriana, viabilidade às condições gastrointestinais e adsorção de AFB1. Todas as estirpes de S. cerevisiae mostraram boa capacidade de autoagregação e coagregação com bactérias patogênicas. Todas as estirpes de levedura foram capazes de sobreviver às condições gastrointestinais. Em condições ácidas, os fatores (cepa x tempo) tiveram interação (P=0,0317), resultando em variações significativas entre as cepas testadas nos períodos de tempo analisados. Observou-se que também houve interação (P=0,0062) em condições intestinais, havendo um aumento do número de células no período de 12h para todas as cepas avaliadas. No ensaio de adsorção, a estirpe A8L2 foi a mais eficaz estatisticamente (P<0,005), para as duas concentrações de AFB1 avaliadas neste estudo (10 e 25ng. mL-1). Dessa forma, conclui-se que as cepas de Saccharomyces cerevisiae possuem potencial probiótico e adsorvente de AFB1.(AU)

In vivo amelioration of aflatoxin B1 in broiler chicks by magnetic carbon nanocomposite

In this study an Iron oxide/carbon nanocomposite from maize straw was prepared and was characterized by XRD, SEM, EDX, FTIR, TG/DTA and Surface area analyzer. The adsorbent was fed to different groups of poultry birds along with aflatoxin B1. Different physiological and blood parameters were monitored in order to study the efficacy of the prepared adsorbent for binding of aflatoxin B1 in the gastrointestinal tract of chickens. It was found that adsorbent at dose of 0.3%/ kg feed was highly effective in detoxifying aflatoxin B1 in gastrointestinal tract of poultry birdswith no harmful effects. The high doses given to groups E and F; 0.4% and 0.5% respectively showed slight variation in tested parameters from group A. No negative symptoms associated with the use of activated carbon as previously reported were observed for the adsorbent under study.(AU)

Inactivación de aflatoxina B1 y aflatoxicol por nixtamalización tradicional del maíz y su regeneración por acidificación de la masa / Inactivation of aflatoxin B1 and aflatoxicol through traditional

OBJETIVO: Confirmar el efecto de la nixtamalización tradicional sobre la aflatoxina, identificar el compuesto remanente en masa, evaluar su toxicidad y su regeneración por tratamiento ácido. MATERIAL Y MÉTODOS: Se utilizó maíz, sin y con aflatoxina, y se nixtamalizó. La toxicidad se evaluó en pollos de ocho días de edad. Se aplicó el tratamiento ácido a la masa. La cuantificación de aflatoxinas se realizó por cromatografía líquida de alta resolución (HPLC). RESULTADOS: La nixtamalización destruyó la aflatoxina (96 por ciento) y el aflatoxicol (70 por ciento); el remanente en masa fue aflatoxina B1. El tratamiento ácido in vitro no eleva las concentraciones de ninguna de las dos micotoxinas. Los pollos murieron al ingerir 260 mg de AFB1, y la masa con aflatoxina remanente no fue tóxica. CONCLUSIONES: Los resultados ilustran el beneficio de la nixtamalización tradicional en la inactivación de las aflatoxinas presentes en maíz y en su no reconstitución por efecto del tratamiento ácido.

Inhibition of microsomal activation of aflatoxin B1 by 3-dehydroretinol and 3-dehydroretinyl palmitate.

Two vitamin A2 compounds (3-dehydroretinol and 3-dehydroretinyl palmitate) which are predominantly present in fresh water fish have been found to be very effective in inhibiting the microsome catalysed formation of DNA adduct by the carcinogen aflatoxin B1. The inhibition appears to be due to modulation of microsomal enzymes which activate the carcinogen. Such inhibition may suggest a potential chemopreventive role of these compounds against carcinogenesis induced by aflatoxin B1.